JP6029017B2 - Earth structure - Google Patents

Description

  The present invention relates to a ground structure.

  2. Description of the Related Art Conventionally, a connector incorporating a filter element such as a capacitor or a coil for removing noise is known in an automobile or the like. The following patent document 1 can be mentioned as an example of such a connector. The connector disclosed here also incorporates a ground terminal connected to the filter element, and the ground terminal is further grounded by being connected to a metal vehicle frame.

JP 2012-39201 A

  By the way, recently, a frame made of CFRP (carbon fiber reinforced resin) is being developed instead of a metal body because of a demand for weight reduction. However, since CFRP is generally electrically insulating, it cannot itself be a ground point. Therefore, in the case of a CFRP frame, it is conceivable to incorporate a grounding conductor inside and use it as a grounding point. Even in that case, it is more effective to increase the degree of freedom of the routing route if the grounding conductor is formed of a flexible member such as a braided wire. However, if the grounding conductor is formed of a flexible member, there is a concern that it is difficult to connect to the ground terminal.

  The present invention has been completed based on the above circumstances, and provides a grounding structure capable of stably connecting a grounding terminal while increasing the degree of freedom of wiring of a grounding conductor. Objective.

The ground structure of the present invention comprises a base member having a mounting opening recessed on one side and a flexible conductive material, and at least a part of the region is exposed to the outside as a ground connection portion. A grounding conductor whose back side is supported by the base member, a grounding member having a grounding terminal connected to the grounding connection part, a receiver embedded and fixed on the backside of the grounding connection part in the base member, and the receiving part And a fixing member composed of a fastener that clamps and fixes the ground terminal and the grounding conductor between and the receiving member.

  In the present invention, when the grounding conductor fixed inside the base member has flexibility, the grounding conductor and the grounding member are connected as follows. First, the mounting opening is opened only on one side of the base member, and one side of the grounding conductor is exposed as a ground connection. That is, since the other side surface of the grounding conductor is supported inside the base member, the grounding member can be stably placed on the ground connection portion through the mounting opening. Then, if the fastener is locked with the ground terminal and the grounding conductor sandwiched between the base member and the receiving member fixed to the corresponding part on the inner surface side of the ground connection portion, the ground terminal is connected to the ground. The external device can be grounded by being fixed to the unit.

  As described above, according to the present invention, since the grounding conductor has flexibility, it is easy to perform the three-dimensional wiring, and the degree of freedom of the wiring route can be easily increased. In addition, the inner surface side of the ground connection portion of the grounding conductor is supported by the base member, and the receiver is provided in a state of being fixed to the base member. Since the conductor can be sandwiched and fixed, the ground terminal can be stably connected.

The top view which shows the earth structure of Example 1 Plan sectional view showing the internal structure of the noise filter Side sectional view showing the periphery of the noise filter mounting section in an enlarged manner Side sectional view showing the ground structure of Example 2 Side sectional view showing the ground structure of Example 3 Side sectional view showing the ground structure of Example 4

A preferred embodiment of the present invention will be described.
(1) In the ground structure of the present invention, a mounting opening is recessed on one side of the base member so that the ground connection portion disposed inside the base member is exposed to the outside. The ground member may be mounted in the mounting opening in a direction in which the longitudinal direction of the ground member is along the longitudinal direction of the base member.
According to such a configuration, since the longitudinal direction of the ground member is aligned with the longitudinal direction of the base member, the opening width in the short direction of the mounting opening can be reduced. Therefore, it is effective for securing the strength of the base member.

(2) The ground member includes a filter element that generates heat when energized and is electrically connected to the ground terminal to remove noise superimposed on the conductor, while the base member includes the ground member. The base member is formed with a resin material having a low thermal conductivity as compared with the main conductor, and the base member is provided with a heat radiating opening that exposes a part of the ground conductor to the outside. It is good.
In the above configuration, since the heat radiation opening is opened in the base member so that a part of the grounding conductor is exposed, even if the filter element provided in the grounding member generates heat by energization, The heat transmitted from the connection portion can be radiated to the outside from the heat radiation opening. Therefore, it is possible to effectively avoid a situation in which the filter element interferes with the filter function due to heat.

(3) The grounding conductor is disposed along the longitudinal direction of the base member, while the heat-dissipating opening is formed in communication with the mounting opening, and the heat-dissipating opening is It is good also as a structure distribute | arranged in the maximum width range of the transversal direction in the opening part for attachment.
According to such a configuration, since the heat radiating opening communicates with the mounting opening, the heat radiating region of the grounding conductor can be continued to enhance the heat radiating effect. In addition, for the base member, there is a concern about strength reduction due to the expansion of the opening area, but since the heat radiation opening is kept within the maximum width range in the short direction of the mounting opening, the necessary strength for the base member is Secured.

(4) The heat radiation opening may be formed such that the side along the longitudinal direction of the base member is long.
According to such a configuration, since the heat radiation opening is formed in an opening shape that is long in the longitudinal direction of the base member and narrow in the lateral direction, it is easy to ensure the width of the base member in the lateral direction. Therefore, it is possible to effectively avoid a decrease in the strength of the base member while securing a necessary heat radiation area by the heat radiation opening.

  Next, Embodiments 1 to 4 embodying the ground structure of the present invention will be described with reference to the drawings.

<Example 1>
1 to 3 show Embodiment 1 of the present invention. FIG. 1 shows a peripheral portion of a ground structure applied to a base member 1 as a vehicle frame of an automobile. In FIG. 1, a part of the base member 1 is shown, which is a long member whose longitudinal direction is the horizontal direction in the drawing. The base member 1 uses carbon fiber reinforced resin (CFRP) as a main material, and is molded using, for example, an epoxy resin or the like as a base material and carbon fiber as a reinforcing material.

  As shown in FIG. 1, the base member 1 has a grounding conductor 2 built in along the longitudinal direction. The grounding conductor 2 in this embodiment is knitted in a cloth shape with conductive fibers, and has conductivity and itself has good flexibility. The grounding conductor 2 is formed in a long band shape having a substantially uniform width, and is excellent in thermal conductivity as compared with the base member 1. The base member 1 of the present embodiment is molded with the grounding conductor 2 embedded therein. Specifically, the grounding conductor 2 is positioned in the center with respect to the thickness direction and the width direction (vertical direction in FIG. 1) of the base member 1.

  As shown in FIG. 1, a mounting opening 4 for attaching a noise filter 3 (grounding member) to be described later is formed on one side of the base member 1 (front side: upper side in FIG. 1). Yes. The mounting opening 4 is formed in a substantially elliptical shape in plan view, and has a depth that exposes the surface side of the grounding conductor 2 to the outside. A region of the ground conductor 2 exposed by the mounting opening 4 is a ground connection portion 5.

  As shown in FIG. 1, the maximum width in the short direction of the mounting opening 4 is H1, and the total dimension 2H2 in the short direction of the base member 1 at the position where the maximum width is reached (of the base member 1 for mounting). It is set to be substantially equal to or smaller than the sum of the dimensions of both regions sandwiching the portion having the maximum width of the opening in the short direction.

  As shown in FIG. 2, the noise filter 3 is attached to the ground connection portion 5. The noise filter 3 in this embodiment is configured as a connector and has a housing 6 made of synthetic resin. The interior of the housing 6 is composed of a capacitor housing chamber 8 for housing the capacitor 7 and a terminal housing chamber 10 from which the tip of the male terminal fitting 9 projects. The male terminal fitting 9 can be connected to a female terminal fitting 11 inserted into the terminal accommodating chamber 10, and the female terminal fitting 11 is connected to an external device via an electric wire 14.

  A pair of leads 12A and 12B are led out from the capacitor 7 housed in the capacitor housing chamber 8. Among these, one lead 12 </ b> A is connected to the ground terminal 13, and the other lead 12 </ b> B is connected to the male terminal fitting 9. The capacitor 7 generates heat when energized, and corresponds to the filter element of the present invention. On the other hand, a lance 15 is formed in the terminal accommodating chamber 10 and can be elastically locked to the female terminal fitting 11 to prevent the female terminal fitting 11 from coming off.

  The ground terminal 13 projects outward from the housing 6, specifically, as shown in FIG. 2 and the like, on the side opposite to the side where the capacitor 7 is accommodated. As shown in FIG. 3, the portion where the ground terminal 13 protrudes from the housing 6 is substantially flush with the bottom surface of the housing 6, and a circular bolt hole 16 is formed therethrough. The noise filter 3 is formed such that the protruding direction of the ground terminal 13 is the longitudinal direction, and is attached to the ground connection portion 5 by a fixing member 20 constituted by a stud bolt 18 and a nut 19. As shown in FIG. 1, the direction in which the noise filter 3 is attached to the ground connection portion 5 is such that the longitudinal direction of the noise filter 3 is along the longitudinal direction of the attachment opening 4.

  As shown in FIG. 3, a through hole 17 that can be aligned with the bolt hole 16 of the ground terminal 13 penetrates at a position near one end in the longitudinal direction (the left end in FIG. 1) in the ground connection portion 5. Is formed. A stud bolt 18 (receiving member) is embedded and fixed in the base member 1 immediately below the through hole 17. The stud bolt 18 is embedded in the base member 1 together with the grounding conductor 2 when the base member 1 is molded. The stud bolt 18 shown in the figure is divided into two with a head portion 18A having a gap in the axial direction, and the formed meat of the base member 1 enters the gap between them to enhance the function of preventing the stud bolt 18 from coming off. Further, a knurled groove is engraved on the outer peripheral surface of the head 18A of the stud bolt 18 so that the function of preventing rotation with respect to the stud bolt 18 is enhanced. The shaft portion 18B of the stud bolt 18 can pass through the through hole 17 and the bolt hole 16 of the ground terminal 13. By tightening a nut 19 (fastener) from the tip of the shaft portion 18B, the shaft portion 18B is connected to the bolt head portion 18A. Thus, the ground terminal 13 and the grounding conductor 2 are sandwiched and held. As a result, the noise filter 3 is fixed to the ground connection portion 5. As shown in FIG. 3, when the noise filter 3 is mounted in the mounting opening 4, the depth of the mounting opening 4 is set so that the noise filter 3 does not protrude from the upper surface of the base member 1. Yes.

  In the base member 1, a pair of heat radiation openings 21 are formed on the surface of the base member 1 where the attachment openings 4 are formed, with the attachment openings 4 sandwiched in the longitudinal direction. Both the heat radiation openings 21 are formed in communication with both ends in the longitudinal direction of the attachment opening 4. Both the heat radiation openings 21 are formed with a depth that exposes the surface of the grounding conductor 2, similar to the attachment opening 4. A region of the grounding conductor 2 exposed by both the heat radiation openings 21 constitutes a heat radiation region. Both the heat radiation openings 21 are formed so as to be narrower than the maximum width in the short direction of the attachment opening 4 and with a substantially uniform width along the longitudinal direction, and the respective tip portions are formed in a semicircular shape. Has been. Both the heat radiation openings 21 are formed such that the dimension along the longitudinal direction of the base member 1 is longer than the dimension along the lateral direction. Further, the entire opening region from the mounting opening 4 to both the heat radiating openings 21 is formed symmetrically with respect to the respective central axes in the longitudinal direction and the short direction of the base member 1.

  Next, the effect of Example 1 comprised as mentioned above is demonstrated. In attaching the noise filter 3, first, the noise filter 3 is stored in the attachment opening 4 so that the longitudinal direction thereof is directed to the longitudinal direction of the attachment opening 4. Then, the bolt hole 16 of the ground terminal 13 in the noise filter 3 is passed through the shaft portion 18B of the stud bolt 18. Thereafter, when the nut is tightened with respect to the shaft portion 18B, the ground terminal 13 and the grounding conductor 2 are sandwiched and held between the head 18A of the stud bolt 18. As a result, the grounding terminal 13 is electrically connected to the grounding conductor 2 to be grounded. Therefore, noise generated in the electrical equipment and superimposed on the wire 14 is removed via the capacitor 7 and grounding. Is done.

  On the other hand, the capacitor 7 generates heat with energization. Since the CFRP constituting the base member 1 has lower thermal conductivity than the ground conductor 2 which is a metal material, the heat generated in the capacitor 7 passes through the bottom surface of the housing 6 rather than being transferred to the base member 1. It is transmitted exclusively to the ground connection 5. In the case of the present embodiment, the grounding conductor 2 is provided with a pair of heat radiation regions (regions where the grounding conductor 2 is exposed by the heat radiation opening 21) continuous to the ground connection portion 5 and both are exposed to the outside. Therefore, the heat transmitted to the ground connection portion 5 is radiated to the outside from both the heat radiation areas. Therefore, it is possible to avoid a situation in which the function as the noise filter 3 is hindered without the capacitor 7 becoming abnormally high heat.

  In the case of the present embodiment, the base member 1 has a structure in which the mounting opening 4 and the heat radiation opening 21 are continuously opened on both sides thereof, so that the strength of the base member 1 is reduced by the opening. Is hard to avoid. In particular, there is a concern when the short dimension of the base member 1 is small as in this embodiment.

  However, in the case of the present embodiment, the attachment opening 4 is formed in an elliptical shape along the longitudinal direction of the base member 1, and the noise filter 3 is attached in the direction in which the longitudinal direction is along the long side of the ellipse. Therefore, the maximum width in the short direction of the mounting opening 4 can be minimized. This contributes to making the width of the thick portion (total value 2H2) substantially equal to or slightly larger than the width (H1) of the opening at the maximum width, and ensuring the strength of the base member 1. It is illustrated.

  Further, since both the heat radiation openings 21 are formed in an elongated shape in the longitudinal direction so as to secure a heat radiation area, the short direction of the base member 1 in the region corresponding to the formation range of both the heat radiation openings 21 is ensured. Can be wide. This is also effective for securing the strength of the base member 1.

<Example 2>
FIG. 4 shows a second embodiment of the present invention. In Example 1, the receiver of the present invention was the stud bolt 18 and the fastener was the nut 19. In the second embodiment, contrary to the first embodiment, the receiving tool is a nut 30 and the fastening tool is a bolt 31. The nut 30 (for example, a hexagonal nut) in the second embodiment is embedded and fixed to the base member 1 while being prevented from rotating. Further, a concave groove 32 is formed along the entire circumference on the outer peripheral surface of the nut 30, and the nut 30 is prevented from coming off by allowing the molded meat of CFRP to bite into the concave groove 32.
Other configurations are the same as those of the first embodiment, and the same operational effects can be exhibited.

<Example 3>
FIG. 5 shows a third embodiment of the present invention. The receiving member in the third embodiment is a cylindrical sleeve 40, and a retaining edge 41 is formed on the lower edge. A sleeve 40 as a receiving member is embedded and fixed in the base member 1, and a retaining edge 41 is hooked to the base member 1 to prevent it from coming off. On the other hand, the fastener is a press-fit pin 42 with a flange 43, and the press-fit pin 42 presses the ground terminal 13 by the flange 43 and the shaft portion is press-fitted into the sleeve 40, so that the end portion of the sleeve 40 is interposed. The ground terminal 13 and the grounding conductor 2 are sandwiched and held.
Other configurations are the same as those of the other embodiments, and the same operational effects can be exhibited.

<Example 4>
FIG. 6 shows a fourth embodiment of the present invention. In the fourth embodiment, a partial length region of the grounding conductor 2 is bent from the inside of the base member 1 to the surface side and exposed to the surface of the base member 1 to constitute the ground connection portion 50. ing. Therefore, in the fourth embodiment, the mounting opening 4 and the heat radiation opening 21 as in the first embodiment are not formed. Other configurations are the same as those of the first embodiment.

  In the fourth embodiment having the above-described configuration, the ground conductor 2 can be easily arranged in a three-dimensional manner so that the ground conductor 2 is directly exposed to the surface of the base member 1 by using the flexibility of the ground conductor 2. it can. Accordingly, it is not necessary to provide openings for reducing the strength of the base member 1 such as the mounting opening 4 and the heat radiating opening 21, thereby ensuring the strength of the base member 1 and simplifying the structure of the base member 1. be able to.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) In the said Example, the noise filter 3 of the format which incorporated the capacitor | condenser 7 which is a filter element in the connector was illustrated. However, the noise filter 3 itself does not necessarily require a connector function. The noise filter 3 and the ground terminal 13 may be incorporated in a simple case.
(2) In the first to third embodiments, the pair of mounting openings 4 are provided with the heat radiation opening 21 interposed therebetween. However, the mounting openings 4 may be provided only on one side.
(3) Although the capacitor 7 is exemplified as the filter element in the above embodiment, the filter element may be a coil.
(4) In the above embodiment, the case where CFRP is formed as the main material as the base member has been described, but it may be formed of other materials. In short, the base member may be formed of a resin material having a lower thermal conductivity than the grounding conductor.

DESCRIPTION OF SYMBOLS 1 ... Base member 2 ... Conductor for earthing 3 ... Noise filter (earthing member)
4 ... Opening for mounting 5 ... Ground connection 7 ... Capacitor (filter element)
13 ... Earth terminal 18 ... Stud bolt
19 ... Nut (fastener)
20 ... Fixing member 21 ... Heat dissipation opening 30 ... Nut (receiver)
31 ... Bolt (fastener)
40 ... Sleeve (Receiver)
42 ... Press-fit pin (fastener)
50 ... Earth connection

Claims (5)

A base member with a mounting opening recessed on one side;
Made of flexible conductive material, with at least a part region is exposed to the outside as a ground connection, the ground conductor back side of the ground connection portion is supported by said base member,
An earth member having an earth terminal connected to the earth connection portion;
A receiving member embedded and fixed on the back surface side of the ground connection portion in the base member, and a fastener that is fixed to the receiving member by sandwiching the ground terminal and the grounding conductor between the receiving member and the receiving member. A grounding structure comprising: a fixing member made of: On one side of the base member, a mounting opening is recessed to expose the ground connection portion arranged inside the base member to the outside,
2. The grounding structure according to claim 1, wherein the grounding member is mounted in the mounting opening so that the longitudinal direction of the grounding member is oriented along the longitudinal direction of the base member. The ground member includes a filter element that generates heat when energized and is electrically connected to the ground terminal to remove noise superimposed on the conductor,
The base member is formed mainly of a resin material having a lower thermal conductivity than the ground conductor, and the base member has a heat dissipation opening that exposes a part of the ground conductor to the outside. The ground structure according to claim 1, wherein the ground structure is formed. While the grounding conductor is disposed along the longitudinal direction of the base member,
The opening for heat dissipation is formed in communication with the opening for attachment, and the opening for heat dissipation is disposed within a maximum width range in the short direction of the opening for attachment. The ground structure according to claim 3.   The ground structure according to claim 3 or 4, wherein the heat radiation opening is formed so that a side along a longitudinal direction of the base member is long.

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